The invention relates to a loop-forming closure element for hook-and-loop fasteners, comprising an embossed nonwoven material having continuous fibers of a spun bonded fabric and carded staple fibers.
For use on diapers, loop-forming closure elements are attached on the front waist region of the diapers in the form of strips. The hook-and-loop fastener is completed by closure strips, which are fastened on the sides of the diapers and have gripping hooks on the free ends thereof. Since the gripping hooks come to lie on the loop-forming closure element during use and bring about an interlocking connection there, the loop-forming closure element is also referred to as a “landing zone”.
Hook-and-loop fasteners are repeatedly opened and closed without this impairing the functionality of the closure. In contrast to adhesive closures, hook-and-loop fasteners are insensitive to contact with skin creams or powder.
A plurality of requirements are placed on hook-and-loop fasteners on disposable products. First of all, it should be possible to produce the loop-forming closure element of the hook-and-loop fastener as simply as possible and using the least amount of material possible, for reasons of cost. Furthermore, the loop-forming closure element must ensure an adequate interconnection with gripping hooks of the associated closure strip. Finally, the closure element should also allow an attractive design to be obtained and should have a pleasant feel.
Document DE 20 2004 021 382 U1 makes known a loop-forming closure element, which has a knitted fabric on a carrier film, wherein the knitted fabric and the carrier film are interconnected by an adhesive pattern. The knitted fabric can have a mass per unit area of 18 g/m2, for example, which results in a lightweight, open structure overall, while a decorative impression on the carrier film remains visible through the knitted fabric. By applying adhesive in a pattern, it is ensured that the loops do not stick to the adhesive-free regions and remain freely accessible for gripping hooks, wherein gripping hooks can even engage in the basic structure of the knitted fabric. On the bonded sections, however, as much adhesive is provided that is necessary to securely fasten the knitted fabric. The fact that individual loops also become bound into the adhesive there is not unacceptable.
Loop-forming closure elements with incorporated loops have proven effective in practical applications, but the feel thereof is perceived as somewhat unpleasant. Even if the loop-forming closure element comes into direct contact with a user only in exceptional cases, the “skin friendliness” of the material still needs improvement for some applications.
In addition to closure elements having incorporated loops, nonwoven materials also are known, which form loops that are suitable for connection with gripping hooks.
Document EP 0 963 472 B1 makes known a loop-forming nonwoven material for hook-and-loop fasteners, wherein bicomponent fibers are used to produce a sufficiently solid structure. In order to obtain a plurality of bonds between fibers, a polymer component is fused onto the bicomponent fibers in the presence of hot air. The manufacturing process is complex overall.
Document WO 03/105621 A1 makes known a spunlaced nonwoven as the loop-forming closure element, wherein the loops are formed by water-jet entangling. The nonwoven material is embossed for decorative purposes. The surface texture and the gripping effect of the known nonwoven material require further improvement.
A loop-forming closure element also is known from DE 10 2004 053 469 A1, wherein a card web, i.e., a layer of carded staple fibers, is disposed on a spun bonded fabric and the thusly formed nonwoven material is embossed. The card web and the spun bonded fabric are provided for different purposes. While the carded staple fibers are provided for connection with gripping hooks, the continuous fibers of the spun bonded fabric provide high stability and attachment on a carrier layer.
Document EP 0 937 420 A2 makes known a loop-forming closure element for hook-and-loop fasteners, which can contain a nonwoven material having continuous fibers of a spun bonded fabric and carded staple fibers. A mechanical needle punching for forming loops is described.